From 92fbd59a57a8906c63ff467eef83f8ed32b92bf9 Mon Sep 17 00:00:00 2001
From: "Enrico Weigelt, metux IT consult" <info@metux.net>
Date: Thu, 13 Mar 2025 13:13:47 +0100
Subject: [PATCH] dix: let FreeGCperDepth() operate on ScreenPtr and NULL
 protect it

Instead of retrieving the screen index from ScreenRec and passing this,
so the ScreenRec is looked up again, just pass in the ScreenPtr that
already have anyways.

Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>
---
 dix/gc.c      | 7 ++++---
 dix/gc_priv.h | 2 +-
 dix/main.c    | 2 +-
 3 files changed, 6 insertions(+), 5 deletions(-)

diff --git a/dix/gc.c b/dix/gc.c
index 014c6d0a7..ecaee32fb 100644
--- a/dix/gc.c
+++ b/dix/gc.c
@@ -821,13 +821,14 @@ CreateScratchGC(ScreenPtr pScreen, unsigned depth)
 }
 
 void
-FreeGCperDepth(int screenNum)
+FreeGCperDepth(ScreenPtr pScreen)
 {
     int i;
-    ScreenPtr pScreen;
     GCPtr *ppGC;
 
-    pScreen = screenInfo.screens[screenNum];
+    if (!pScreen)
+        return;
+
     ppGC = pScreen->GCperDepth;
 
     for (i = 0; i <= pScreen->numDepths; i++) {
diff --git a/dix/gc_priv.h b/dix/gc_priv.h
index 18d5fefbe..52b6f22a4 100644
--- a/dix/gc_priv.h
+++ b/dix/gc_priv.h
@@ -22,7 +22,7 @@ int CopyGC(GCPtr pgcSrc, GCPtr pgcDst, BITS32 mask);
 
 int FreeGC(void *pGC, XID gid);
 
-void FreeGCperDepth(int screenNum);
+void FreeGCperDepth(ScreenPtr pScreen);
 
 Bool CreateGCperDepth(int screenNum);
 
diff --git a/dix/main.c b/dix/main.c
index 0c57ba605..8b953dbf3 100644
--- a/dix/main.c
+++ b/dix/main.c
@@ -327,7 +327,7 @@ dix_main(int argc, char *argv[], char *envp[])
         }
 
         for (i = screenInfo.numScreens - 1; i >= 0; i--) {
-            FreeGCperDepth(i);
+            FreeGCperDepth(screenInfo.screens[i]);
             FreeDefaultStipple(i);
             dixFreeScreenSpecificPrivates(screenInfo.screens[i]);
             (*screenInfo.screens[i]->CloseScreen) (screenInfo.screens[i]);